The elections manager of Nyandarua County has postponed announcement of final results to Friday.
Mr Gideon Balang said his officers are fatigued and he could not overwork them past 6pm.
"I cannot overwork my staff. These people have been here since day one. They also need some rest," he said.
By around 5pm Thursday, Mr Balang was not sure of receiving results from three constituencies - Kinangop, Kipipiri and Ol Kalou.
He appealed to voters and candidates to be patient, assuring them nothing fishy was going on.
"I appreciate the patience exhibited by the candidates. I appeal to them to allow us some more time. It is a very tedious exercise, which must be conducted to perfection," Mr Balang said.
By early afternoon, the county tallying centre was nearly deserted as agents and observers joined other Kenyans in following results of various positions.
But the parliamentary winners of the five constituencies were announced by returning officers.
In Ol Kalou, Mr David Kiaraho of Jubilee retained his seat (he got 37,751 votes) while Mr John Waiganjo lost the Ol Jorok seat to Mr Michael Muchira.
The former secured 14,176 votes and the latter 31,532 votes.
Former minister Amos Kimunya got 30,663 votes to win the Kipipiri parliamentary post.
Mr Zachary Kweya captured the Kinangop seat (73,204 votes), while Mr Jeremiah Kioni made a political comeback after winning the Ndaragwa seat with 30,668 votes.
All the candidates are Jubilee Party members.